Chelsea returns to Premier League action after a two-week international break protecting a four-point lead at the top of the table but with injury problems in defense ahead of tough trip to Aston Villa on Saturday.
Their cause has been made more difficult with John Terry and Alex nursing injuries that will force manager Carlo Ancelloti into playing a makeshift center-half pairing.
City visits Blackpool on Sunday looking to take advantage of any Chelsea slip-up while third-place Manchester United is a further point behind, ahead of its home match against West Bromwich Albion.
Alex will be out for at least another week with a thigh injury sustained in the win over Arsenal before the international hiatus, while Terry is a major doubt after missing England's European Championship qualifier on Tuesday with a back problem.
It means central midfielder Michael Essien or full back Paulo Ferreira could play in the middle alongside Branislav Ivanovic, who usually operates at right back.
Villa is unbeaten at home this season and promising right-winger Marc Albrighton is confident his team can shock the leaders.
"The lads will relish going out against Chelsea at Villa Park," Albrighton said. "It will probably be a full house against the top team in the Premier League at the minute.
"They are absolutely flying. We'll go out there as the underdogs but we'll relish that and hopefully we'll get a few points off them."
City moved above neighbor United in the table by edging past Newcastle 2-1 a fortnight ago and will start as favorites against promoted side Blackpool, which upset Liverpool away last time out.
City midfielder Yaya Toure isn't expecting an easy ride at Bloomfield Road.
"Blackpool are a good team. It's not easy to play against a team like that - they have been a big surprise and won 2-1 at Anfield," Toure said.
"That's not an easy result to get (so) they will be tough."
United's match against West Brom could herald a return for Owen Hargreaves, who has not started a first-team game since September 2008 because of a chronic knee injury.
Wayne Rooney should also start after playing for England in midweek. The striker has not played for United since being substituted in the 2-2 draw against Bolton on Sept. 26.
At the other end of the table, Liverpool striker Fernando Torres should make his return from injury in Sunday's derby match against Everton as the 18-time champions look to end a dramatic week off the pitch by reviving their league fortunes on it.
While the Reds' ownership battle rumbles on after a week of twists and turns in the courtroom, the players must direct their focus on beating the club's local rivals - who are fourth from bottom - and climbing not only above them but also out of the relegation zone.
The return of Torres will be a major fillip for manager Roy Hodgson, who is already under pressure after third-bottom Liverpool's poor start to the season.
The oft-injured Spain striker has never regained full fitness since being carried off on a stretcher with a groin strain during the World Cup final against the Netherlands in July.
"Fernando's season needs to kickstart, he's been hampered a bit by injuries and what happened at the World Cup," Hodgson said. "We see a livelier and a better Fernando every day."
On Saturday, fourth-place Arsenal hosts Birmingham, bottom club West Ham visits second-bottom Wolverhampton, Bolton hosts Stoke, Fulham is at home to Tottenham and Wigan is at Newcastle.
On Monday, Blackburn hosts Sunderland.
